Inter-transceiver module communication for firmware upgrade

ABSTRACT

An operational optical transceiver configured to update operational firmware using an optical link of the transceiver. The optical transceiver includes at least one processor and a system memory capable of receiving firmware. The optical transceiver receives an optical signal over the optical link containing the update firmware. The optical transceiver then recovers the firmware from the optical signal. Finally, the optical transceiver provides to the system memory the recovered firmware, which when executed by the at least one processor alters the operation of the transceiver.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.11/241,086, filed Sep. 30, 2005, which claims the benefit of U.S.Provisional Application No. 60/623,256, filed Oct. 29, 2004, bothapplications which are incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates generally to optical transceivers. Morespecifically, the present invention relates to upgrading operationalfirmware in an optical transceiver using an optical link.

2. The Relevant Technology

Computing and networking technology have transformed our world. As theamount of information communicated over networks has increased, highspeed transmission has become ever more critical. Many high speed datatransmission networks rely on optical transceivers and similar devicesfor facilitating transmission and reception of digital data embodied inthe form of optical signals over optical fibers. Optical networks arethus found in a wide variety of high speed applications ranging from asmodest as a small Local Area Network (LAN) to as grandiose as thebackbone of the Internet.

Typically, data transmission in such networks is implemented by way ofan optical transmitter (also referred to as an electro-optictransducer), such as a laser or Light Emitting Diode (LED). Theelectro-optic transducer emits light when current is passed therethrough, the intensity of the emitted light being a function of thecurrent magnitude. Data reception is generally implemented by way of anoptical receiver (also referred to as an optoelectronic transducer), anexample of which is a photodiode. The optoelectronic transducer receiveslight and generates a current, the magnitude of the generated currentbeing a function of the intensity of the received light.

Various other components are also employed by the optical transceiver toaid in the control of the optical transmit and receive components, aswell as the processing of various data and other signals. For example,such optical transceivers typically include a driver (e.g., referred toas a “laser driver” when used to drive a laser signal) configured tocontrol the operation of the optical transmitter in response to variouscontrol inputs. The optical transceiver also generally includes anamplifier (e.g., often referred to as a “post-amplifier”) configured toperform various operations with respect to certain parameters of a datasignal received by the optical receiver. A controller circuit(hereinafter referred to the “controller”) controls the operation of thelaser driver and post amplifier.

Controllers are typically implemented in hardware as state machines.Their operation is fast, but inflexible. Being primarily state machines,the functionality of the controller is limited to the hardware structureof the controller. What would be advantageous are controllers that havemore flexibility to change their functionality.

BRIEF SUMMARY OF THE INVENTION

The forgoing problems with the prior state of the art are overcome bythe principles of the present invention, which relate to an opticaltransceiver configured to receive firmware updates using its opticallink. The optical transceiver includes at least one processor and asystem memory. The system memory is configured to receive firmware overthe optical link that, when executed by the processor, may alter theoperation of the optical transceiver.

The optical transceiver receives an optical signal containing firmwarefrom a source such as another optical transceiver, a host computingsystem, or a separate programming unit. The optical transceiver thenrecovers the firmware from the optical signal and provides the recoveredfirmware to the system memory. The optical transceiver, specifically theprocessor, may then execute the recovered firmware. As mentioned, theexecuted firmware is structured to alter the operation of the opticaltransceiver.

Accordingly, there are many advantages to the principles of the presentinvention. For example, the process removes the need to exclusively usean electrical link between the optical transceiver and a host computingsystem for firmware updates. This is especially useful for opticaltransceivers that may not have a direct electrical link with the host.In addition, the principles of the present invention allow for theupdating of firmware to an optical transceiver that is installed in aremote or inaccessible location, such as an optical transceiver on theocean floor.

Additional features and advantages of the invention will be set forth inthe description that follows, and in part will be obvious from thedescription, or may be learned by the practice of the invention. Thefeatures and advantages of the invention may be realized and obtained bymeans of the instruments and combinations particularly pointed out inthe appended claims. These and other features of the present inventionwill become more fully apparent from the following description andappended claims, or may be learned by the practice of the invention asset forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 schematically illustrates an example of an optical transceiverthat may implement features of the present invention;

FIG. 2 schematically illustrates an example of a control module of FIG.1; and

FIG. 3 illustrates a flowchart of a method for an optical transceiver touse an optical link to alter its operation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The principles of the present invention relate to an operational opticaltransceiver configured to update operational firmware using an opticallink of the transceiver. The optical transceiver includes at least oneprocessor and a system memory capable of receiving firmware. The opticaltransceiver receives an optical signal containing the update firmwareover the optical link. The optical transceiver then recovers thefirmware from the optical signal. Finally, the optical transceiverprovides to the system memory the recovered firmware, which whenexecuted by the at least one processor alters the operation of thetransceiver. An example operational optical transceiver environment willfirst be described. Then, the operation in accordance with the inventionwill be described with respect to the operational environment.

FIG. 1 illustrates an optical transceiver 100 in which the principles ofthe present invention may be employed. While the optical transceiver 100will be described in some detail, the optical transceiver 100 isdescribed by way of illustration only, and not by way of restricting thescope of the invention. The principles of the present invention aresuitable for 1G, 2G, 4G, 8G, 10G and higher bandwidth fiber optic links.Furthermore, the principles of the present invention may be implementedin optical (e.g., laser) transmitter/receivers of any form factor suchas XFP, SFP and SFF, without restriction. Having said this, theprinciples of the present invention are not limited to an opticaltransceiver environment at all.

The optical transceiver 100 receives an optical signal from fiber 110Ausing receiver 101. The receiver 101 acts as an opto-electric transducerby transforming the optical signal into an electrical signal. Thereceiver 101 provides the resulting electrical signal to apost-amplifier 102. The post-amplifier 102 amplifies the signal andprovides the amplified signal to an external host 111 as represented byarrow 102A. The external host 111 may be any computing system capable ofcommunicating with the optical transceiver 100. The external host 111may contain a host memory 112 that may be a volatile or non-volatilememory source. In one embodiment, the optical transceiver 100 may be aprinted circuit board or other components/chips within the host 111,although this is not required.

The optical transceiver 100 may also receive electrical signals from thehost 111 for transmission onto the fiber 110B. Specifically, the laserdriver 103 receives the electrical signal as represented by the arrow103A, and drives the transmitter 104 (e.g., a laser or Light EmittingDiode (LED)) with signals that cause the transmitter 104 to emit ontothe fiber 110B optical signals representative of the information in theelectrical signal provided by the host 111. Accordingly, the transmitter104 serves as an electro-optic transducer.

The behavior of the receiver 101, the post-amplifier 102, the laserdriver 103, and the transmitter 104 may vary dynamically due to a numberof factors. For example, temperature changes, power fluctuations, andfeedback conditions may each affect the performance of these components.Accordingly, the optical transceiver 100 includes a control module 105,which may evaluate temperature and voltage conditions and otheroperational circumstances, and receive information from thepost-amplifier 102 (as represented by arrow 105A) and from the laserdriver 103 (as represented by arrow 105B). This allows the controlmodule 105 to optimize the dynamically varying performance, andadditionally detect when there is a loss of signal.

Specifically, the control module 105 may counteract these changes byadjusting settings on the post-amplifier 102 and/or the laser driver 103as also represented by the arrows 105A and 105B. These settingsadjustments are quite intermittent since they are only made whentemperature or voltage or other low frequency changes so warrant.Receive power is an example of such a low frequency change.

The control module 105 may have access to a persistent memory 106, whichin one embodiment, is an Electrically Erasable and Programmable ReadOnly Memory (EEPROM). The persistent memory 106 and the control module105 may be packaged together in the same package or in differentpackages without restriction. Persistent memory 106 may also be anyother non-volatile memory source.

The control module 105 includes both an analog portion 108 and a digitalportion 109. Together, they allow the control module to implement logicdigitally, while still largely interfacing with the rest of the opticaltransceiver 100 using analog signals. FIG. 2 schematically illustratesan example 200 of the control module 105 in further detail. The controlmodule 200 includes an analog portion 200A that represents an example ofthe analog portion 108 of FIG. 1, and a digital portion 200B thatrepresents an example of the digital portion 109 of FIG. 1.

For example, the analog portion 200A may contain digital to analogconverters, analog to digital converters, high speed comparators (e.g.,for event detection), voltage based reset generators, voltageregulators, voltage references, clock generator, and other analogcomponents. For example, the analog portion 200A includes sensors 211A,211B, 211C amongst potentially others as represented by the horizontalellipses 211D. Each of these sensors may be responsible for measuringoperational parameters that may be measured from the control module 200such as, for example, supply voltage and transceiver temperature. Thecontrol module may also receive external analog or digital signals fromother components within the optical transceiver that indicate othermeasured parameters such as, for example, laser bias current, transmitpower, receive power, laser wavelength, laser temperature, and ThermoElectric Cooler (TEC) current. Two external lines 212A and 212B areillustrated for receiving such external analog signals although theremay be many of such lines.

The internal sensors may generate analog signals that represent themeasured values. In addition, the externally provided signals may alsobe analog signals. In this case, the analog signals are converted todigital signals so as to be available to the digital portion 200B of thecontrol module 200 for further processing. Of course, each analogparameter value may have its own Analog to Digital Converter (ADC).However, to preserve chip space, each signal may be periodically sampledin a round robin fashion using a single ADC such as the illustrated ADC214. In this case, each analog value may be provided to a multiplexer213, which selects in a round robin fashion, one of the analog signalsat a time for sampling by the ADC 214. Alternatively, multiplexer 213may be programmed to allow any order of analog signals to be sampled byADC 214.

As previously mentioned, the analog portion 200A of the control module200 may also include other analog components 215 such as, for example,digital to analog converters, other analog to digital converters, highspeed comparators (e.g., for event detection), voltage based resetgenerators, voltage regulators, voltage references, clock generator, andother analog components.

The digital portion 200B of the control module 200 may include a timermodule 202 that provides various timing signals used by the digitalportion 200B. Such timing signals may include, for example, programmableprocessor clock signals. The timer module 202 may also act as a watchdogtimer.

Two general-purpose processors 203A and 203B are also included. Theprocessors recognize instructions that follow a particular instructionset, and may perform normal general-purpose operation such as shifting,branching, adding, subtracting, multiplying, dividing, Booleanoperations, comparison operations, and the like. In one embodiment, thegeneral-purpose processors 203A and 203B are each a 16-bit processor andmay be identically structured. The precise structure of the instructionset is not important to the principles of the present invention as theinstruction set may be optimized around a particular hardwareenvironment, and as the precise hardware environment is not important tothe principles of the present invention.

A host communications interface 204 is used to communicate with the host111, possibly implemented using a two-wire interface such as I²C shownin FIG. 1 as the serial data (SDA) and serial clock (SCL) lines on theoptical transceiver 100. Other host communication interfaces may also beimplemented as well. Data may be provided from the control module 105 tothe host 111 using this host communications interface to allow fordigital diagnostics and readings of temperature levels,transmit/receiver power levels, and the like. The external deviceinterface 205 is used to communicate with, for example, other moduleswithin the optical transceiver 100 such as, for example, thepost-amplifier 102, the laser driver 103, or the persistent memory 106.

The internal controller system memory 206 (not to be confused with theexternal persistent memory 106) may be Random Access Memory (RAM) ornon-volatile memory. The memory controller 207 shares access to thecontroller system memory 206 amongst each of the processors 203A and203B and with the host communication interface 204 and the externaldevice interface 205. In one embodiment, the host communicationinterface 204 includes a serial interface controller 201A, and theexternal device interface 205 includes a serial interface controller201B. The two serial interface controllers 201A and 201B may communicateusing a two-wire interface such as I²C or another interface so long asthe interface is recognized by both communicating modules. One serialinterface controller (e.g., serial interface controller 201B) is amaster component, while the other serial interface controller (e.g.,serial interface controller 201A) is a slave component.

An input/output multiplexer 208 multiplexes the various input/outputpins of the control module 200 to the various components within thecontrol module 200. This enables different components to dynamicallyassign pins in accordance with the then-existing operationalcircumstances of the control module 200. Accordingly, there may be moreinput\output nodes within the control module 200 than there are pinsavailable on the control module 200, thereby reducing the footprint ofthe control module 200.

Register sets 209 contain a number of individual registers. Theseregisters may be used by the processors 203 to write firmware generateddata that controls high speed comparison in optical transceiver 100A.Alternatively, the registers may hold data selecting operationalparameters for comparison. Additionally, the registers may be memorymapped to the various components of optical transceiver 100A forcontrolling aspects of the component such as laser bias current ortransmit power.

Having described a specific environment with respect to FIGS. 1 and 2,it will be understood that this specific environment is only one ofcountless architectures in which the principles of the present inventionmay be employed. As previously stated, the principles of the presentinvention are not intended to be limited to any particular environment.The principles of the present invention will be discussed with referenceto the environment described in relation to FIGS. 1 and 2.

Accordingly, the principles of the present invention allow for using anoptical link of the optical transceiver to update firmware, which whenexecuted controls the operation of the optical transceiver. In thedescription and in the claims, “operation” is defined to mean the mannerin which the optical transceiver communicates with the outside world andthe manner in which the optical transceiver internally functions. In thedescription and in the claims, “firmware” is defined to mean any type ofoperational or control code, such as, but not limited to, microcode andsoftware, that runs on a microprocessor and controls the operation ofthe transceiver when executed.

The updated firmware is received over the optical link and then providedto system memory for execution. In the description and in the claims,“system memory” is defined to mean RAM such as controller system memory206, non-volatile memory such as persistent memory 106, a register, aprocessor, a flip-flop, and/or any other type of memory. The principlesof the present invention thus enable efficient firmware updates of anyoptical transceiver regardless of the location of the transceiver or thetransceiver's distance from the host.

There may be many different types of update firmware available. A usermay desire to update transceiver operational firmware. This firmware maydirect, when executed, how transceiver 100 communicates with the outsideworld and how transceiver 100 performs internal functions such asdigital diagnostics. Alternatively, the user may desire to updatefirmware that when executed implements specific transceiver operationalfeatures such as off-transceiver logging or alarm settings. It may alsobe possible to update various other types of transceiver firmware.

Referring again to FIG. 1, a sensor 113 is shown coupled to receiver101. Sensor 113 may be an out-of-band demodulator, a filter, aphoto-diode, or any other type of device capable of detecting andprocessing an optical or electrical signal.

Referring to FIG. 3, a flowchart of a method 300 for altering theoperation of an optical transceiver through the use of an optical linkis illustrated. First, an optical transceiver receives an optical signalover the optical link (act 301). This signal may be received fromanother optical transceiver that is coupled to the optical transceiverby an optical link, a host computing system coupled to the opticaltransceiver by an optical link, or a programming unit coupled to theoptical transceiver by an optical link.

In one embodiment illustrated with respect to FIGS. 1 and 2, transceiver100 receives an optical signal over fiber 110A that is double modulatedto contain a high-speed communication signal and a lower frequencyout-of-band signal containing update firmware. This optical signal maybe produced by a variety of sources. For example, a remote transceivercontrol module may modulate the out-of-band signal comprising the updatefirmware onto the high-speed communication signal. The modulation may beaccomplished by any modulation technique known to one skilled in theart. The out-of-band signal may be modulated at a frequency that is muchslower than the high-speed signal. The double modulated signal is thenconverted to an optical signal by the remote transceiver's transmitterand transmitted to transceiver 100.

Alternatively, the out-of-band signal containing the update firmware maybe modulated onto a high-speed communication signal by host 111 or by aspecial programming unit that is connected directly to the optical link.The special programming unit may be capable of producing both thehigh-speed communication signal and modulating the out-of-band signalcomprising the update firmware onto the high speed signal.

Referring again to the method of FIG. 3, the optical transceiverrecovers update firmware contained in the optical signal (act 302). Therecovery of the update firmware may be accomplished by use of a sensorthat is configured to detect the firmware and recover it from theoptical signal. Examples of such a sensor include, but are not limitedto, a demodulator, a filter, a photo-diode, or any other sensor capableof reading an electric or optical signal. The update firmware may berecovered from the optical signal by any other method known to thoseskilled in the art.

Returning again to the embodiment illustrated with respect to FIGS. 1and 2, fiber 110A may send the doubled modulated signal to receiver 101where the double modulated signal is converted to an electrical signal.The post-amplifier 102 extracts the high speed communication signal andmay send it to host 111 as previously described. However, sensor 113,which in this case may be an out-of-band demodulator, may recover theupdate firmware by demodulating the out-of-band signal from the highspeed communication signal. Sensor 113 may then send the recoveredupdate firmware to control module 105 over line 105C for furtherprocessing. Sensor 113 may be an out-of-band demodulator such as the onedescribed in commonly assigned co-pending U.S. patent application Ser.No. 10/824,258, filed Apr. 14, 2004, which is incorporated herein byreference.

In a second embodiment of the present invention, a firmware update mayalso be accomplished by receiving an optical signal over the opticallink. In this case, an optical signal is produced that comprises twocomponents. This signal may be produced by the control module of aremote transceiver, the host 111, or the special programming unitdescribed above. The first component of the signal would consist ofalternating binary ones and zeroes. This signal may alert transceiver100, specifically control module 105, that a firmware update is about tooccur.

The second component of the optical signal may be a low frequency signalcomprising a long series of binary ones followed by a long series ofbinary zeroes repeated multiple times. The long series of binary onesand zeroes may comprise the update firmware. In a normal signal, sensor113, which may be a filter in this case, would not expect to see morethan a few binary ones or a few binary zeroes in a row. In this case,sensor 113 may detect the long rows of binary ones and zeroes and mayfilter them out of the optical signal. Sensor 113 may send the binaryones and zeroes to control module 105 as the binary numbers are filteredout of the signal.

In a third embodiment of the present invention, optical transceiver 100may receive a high speed optical signal comprising various binary onesand zeroes. This signal may also include update firmware. The signal maycreate a frequency spectrum with a number of frequency harmonics. One ofthe harmonics at a designated frequency may have a binary 1 or a binary0 encoded on it. For example, when the optical signal comprises binaryones, the encoded harmonic may also include a binary 1. Conversely, whenthe optical signal comprises binary zeroes, the encoded harmonic mayinclude a binary 0. Sensor 113, which in this embodiment may be afilter, may filter out each of the binary ones or zeroes from theencoded harmonic. As each bit is filtered out, it may be provided tocontrol module 105 over connection 105C for further processing.

The optical transceiver then provides the recovered update firmware tothe system memory (act 303). For example, referring again to FIGS. 1 and2, the recovered update firmware, regardless of which embodiment wasimplemented to recover the firmware from the optical signal, is sent tocontrol module 105 over connection 105C, which is represented by lines212A and 212B in FIG. 2. The recovered update firmware is then providedto controller system memory 206 for execution.

In some embodiments, transceiver 100 may contain dedicated loaderfirmware, either in persistent memory 106 or a memory location ofcontrol module 105 such as register sets 209 or controller system memory106, which is structured to assist in the loading of the updatefirmware. This dedicated loader firmware may be executed by processors203. The loader firmware may direct processors 203 to check the receivedupdate firmware for errors. If no errors are found, the loader firmwaremay further direct processors 203 to execute the new firmware or to loadthe firmware into persistent memory 106 for later execution. Inembodiments without the loader firmware, the update firmware may bedirectly executed by processors 203 or loaded to persistent memory 106for later execution.

Referring again to the method 300 of FIG. 3, the updated firmware isexecuted by the optical transceiver (act 304). The executed firmware mayalter the operation of transceiver 100 in different ways depending onthe type of update firmware that is executed. For example, suppose thatthe update firmware was structured to update the operational firmware.The firmware would be provided to persistent memory 106 where it wouldoverwrite some or all of the existing operational firmware. Whenexecuted by processors 203, the new operational firmware would alter theoperation of transceiver 100 by changing operational parameters such ashow to transmit and receive optical data. Alternatively, the executedupdate firmware may cause transceiver 100 to implement a specificfeature such as off-transceiver logging of operational parameters.

Accordingly, the principles of the present invention relate to anoperational optical transceiver configured to update operationalfirmware using the optical link. The optical transceiver receives anoptical signal over an optical link containing the update firmware. Theoptical transceiver then recovers the update firmware from the opticalsignal. Finally, the optical transceiver provides the recovered firmwareto the system memory where the processors may execute the firmware. Thisprocess removes the need to exclusively use the electrical link toprovide update firmware to the transceiver. In addition, the principlesof the present invention provide a way that allows for updating firmwareto a transceiver that is not easily accessible or are located a longdistance from the host, such as a transceiver on the ocean floor.Accordingly, the principles of the present invention represent asignificant advancement in the art of optical transceivers.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. An optical transceiver comprising: a systemmemory; at least one processor programmed to execute firmware stored inthe system memory, the executed firmware structured to at leastpartially control the operation of the optical transceiver; wherein theoptical transceiver is configured to alter its operation by: receivingan optical signal over an optical link; recovering firmware from theoptical signal, wherein the recovered firmware is structured such that,when executed by the at least one processor, the operation of theoptical transceiver is altered; providing the recovered firmware tosystem memory; and executing the recovered firmware, wherein the opticaltransceiver further comprises a filter configured to filter out firmwareencoded in a frequency harmonic of the optical signal.
 2. An opticaltransceiver in accordance with claim 1, wherein the optical transceiveris one of a 1G laser transceiver, a 2G laser transceiver, a 4G lasertransceiver, a 8G laser transceiver, or a 10G laser transceiver.
 3. Anoptical transceiver in accordance with claim 1, wherein the opticaltransceiver is a laser transceiver suitable for fiber optic linksgreater than 10G.
 4. An optical transceiver in accordance with claim 1,wherein the optical transceiver is one of a XFP laser transceiver, a SFPlaser transceiver, or a SFF laser transceiver.
 5. An optical transceiverin accordance with claim 1, wherein the at least one processor isfurther programmed to execute loader firmware to check the recoveredfirmware for errors prior to executing the recovered firmware.
 6. Anoptical transceiver in accordance with claim 1, wherein the opticaltransceiver includes loader firmware that is structured to assist inproviding the recovered firmware to the system memory and assist inexecuting the recovered firmware.
 7. An optical transceiver inaccordance with claim 1, wherein executing the recovered firmware altershow the optical transceiver transmits and receives optical data.
 8. Anoptical transceiver in accordance with claim 1, wherein executing therecovered firmware implements a specific operational feature.
 9. Anoptical transceiver in accordance with claim 8, wherein the specificoperational feature includes off-transceiver logging of operationalparameters.
 10. An optical transceiver in accordance with claim 1,wherein the optical transceiver is further configured to store therecovered firmware in a non-volatile memory source that is separate froma control module that includes the system memory prior to executing therecovered firmware.
 11. In an optical transceiver that includes systemmemory and one or more processors, a method for altering the operationof the optical transceiver using an optical link, the method comprising:an act of the optical transceiver receiving an optical signal over theoptical link, the optical signal containing both high-speedcommunication data and embedded harmonic firmware; an act of the opticaltransceiver recovering firmware from the optical signal using a filterthat filters the embedded harmonic firmware from the high-speedcommunication data prior to any post-amplification being performed onthe high-speed communication data; an act of the optical transceiverproviding the recovered firmware to system memory; and an act of the oneor more processors executing the recovered firmware, the recoveredfirmware being structured such that, when executed by the one or moreprocessors, the operation of the optical transceiver is altered.
 12. Amethod in accordance with claim 11, wherein the optical transceiverincludes loader firmware that is structured to assist in providing therecovered firmware to the system memory and assist in the one or moreprocessors executing of the recovered firmware.
 13. A method inaccordance with claim 11, wherein the operation of the opticaltransceiver is altered in how the optical transceiver transmits andreceives optical data.
 14. A method in accordance with claim 11, whereinthe operation of the optical transceiver is altered in how the opticaltransceiver implements a specific operational feature.
 15. A method inaccordance with claim 14, wherein the specific operational featureincludes off-transceiver logging of operational parameters.
 16. A methodin accordance with claim 11, wherein the optical transceiver receivesthe optical signal from one of another optical transceiver that iscoupled to the optical transceiver by the optical link, a host computingsystem coupled to the optical transceiver by the optical link, or aprogramming unit coupled to the optical transceiver by the optical link.17. A method in accordance with claim 11, further comprising an act ofchecking the recovered firmware for errors prior to the act of the oneor more processors executing the recovered firmware.
 18. A method inaccordance with claim 11, further comprising an act of storing therecovered firmware in a non-volatile memory source that is separate froma control module that includes the system memory prior to the act of theone or more processors executing the recovered firmware.